OK, so if I had C_{3}H_{8}(g) + 5O_{2}(g) ---> 3CO_{2}(g) + 4H_{2}O(g)

And I needed to find how much heat is released by burning 10 moles of propane, I would have to balance the equation, and in turn, that would give me like 10C_{3}H_{8} +50O_{2} ---> 30CO_{2} + 40H_{2}0.

Anyway, I would then use Hess's equation and subtract the heat released by each reactant in their standard states (by multiplying by the moles per elements) from the heat released by their products.

Right?